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Defence Technology（防务技术） 2024年第1期31卷 158-162页

作者： Xue Yang Qijun liu Yundan Gan Lei Yang zhengtang liu Fusheng liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031People's Republic of China Xi'an Modern Chemistry Research Institute Xi'an 710065People's Republic of China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072People's Republic of China

As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned *** some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more ***,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.29 *** plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were *** Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 24.96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.

关键词： Powdered TKX-50 Hugoniot Raman Decomposition Phase transition

Evolution of molecular structure of TATB under shock loading from transient Raman spectroscopic technique

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Defence Technology（防务技术） 2024年第3期33卷 613-620页

作者： Hongliang Kang Xue Yang Wenshuo Yuan Lei Yang Xinghan Li Fusheng liu zhengtang liu Qijun liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

By combination of the transient Raman spectroscopic measurement and the density functional theoretical calculations,the structural evolution and stability of TATB under shock compression was *** to the improvement in synchronization control between two-stage light gas gun and the transient Raman spectra acquisition,as well as the sample preparation,the Raman peak of the N-O mode of TATB was firstly observed under shock pressure up to 13.6 GPa,noticeably higher than the upper limit of 8.5 GPa reported in available *** taking into account of the continuous shift of the main peak and other observed Raman peaks,we did not distinguish any structural transition or any new ***,both the present Raman spectra and the time-resolved radiation of TATB during shock loading showed that TATB exhibits higher chemical stability than previous *** reveal the detailed structural response and evolution of TATB under compression,the density functional theoretical calculations were conducted,and it was found that the pressure make N-O bond lengths shorter,nitro bond angles larger,and intermolecular and intra-molecular hydrogen bond interactions *** observed red shift of Raman peak was ascribed to the abnormal enhancement of H-bound effect on the scissor vibration mode of the nitro group.

关键词： TATB Raman spectra Structural evolution Shock loading

Pattern transition and sluggish cracking of colloidal droplet deposition with polymer additives

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1712-1718页

作者： ZHANG YongJian liu zhengtang ZANG DuYang QIAN YiMeng LIN KeJun State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical University Key Laboratory of Space Applied Physics and Chemistry(Ministry of Education) School of ScienceNorthwestern Polytechnical University

Drying of colloidal droplets often develops versatile *** study the drying deposition of both colloidal droplets containing silica nanoparticles and the silica colloidal droplets with polyethylene oxide(PEO) *** focus on the effect of polymer additives on the deposition formation and the cracking dynamics by using in-situ microscope *** PEO additives,a transition from ring-like deposition to uniform deposition is observed,and the cracking dynamics is greatly *** PEO additives enhance the adsorption of particles at the air-water interface,thus forming the network structure at the interface which blocks the outward capillary *** contributes to the uniform ***,the multi-distribution of the aggregates size enhances the non-homogeneity of the drying film and consequently results in multi-nucleation of *** reduces the stress accumulation that drives the crack propagation and may be responsible for the sluggish cracking dynamics.

关键词： sessile droplet drying crack pattern coffee effect

Properties of Gallium Phosphide Thick Films Prepared on Zinc Sulfide Substrates by Radio-Frequency Magnetron Sputtering

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Journal of Materials Science & Technology 2010年第1期26卷 93-96页

作者： Yangping Li and zhengtang liu School of Materials Science and Engineering, Northwestern Polytechnical University, Xi an 710072, China [a] School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

Radio-frequency （RF） magnetron sputtering was employed to prepare gallium phosphide （GAP） thick films on zinc sulfide （ZnS） substrates by sputtering a single crystalline GaP target in an Ar atmosphere. The infrared （IR） transmission properties, structure, morphology, composition and hardness of the film were studied. Results show that both amorphous and zinc-blende crystalline phases existed in the GaP film in almost stoichiometric amounts. The GaP film exhibited good IR transmission properties, though the relatively rough surface and loose microstructure caused a small loss of IR transmission due to scattering. The GaP film also showed a much higher haraness than the ZnS substrate, thereby providing good protection to ZnS.

关键词： Radio-frequency magnetron sputtering Gallium phosphide Thick film Infrared transmission

Rain Erosion Behavior of Silicon Dioxide Films Prepared on Sapphire

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Journal of Materials Science & Technology 2005年第6期21卷 883-886页

作者： Liping FENG+, zhengtang liu and Wenting liu Laboratory of Functional Materials, College of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an710072, China Laboratory of Functional Materials College of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

Silicon dioxide （SiO2） films were prepared on sapphire （α-Al2O3） by radio frequency magnetron reactive sputtering in order to increase both transmission and rain erosion resistant performance of infrared domes of sapphire. Composition and structure of SiO2 films were analyzed by X-ray photoelectron spectroscopy （XPS） and X-ray diffraction （XRD）, respectively. The transmittance of uncoated and coated sapphire was measured using a Fourier transform infrared （FTIR） spectrometer. Rain erosion tests of the uncoated and coated sapphire were performed at 211 m/s impact velocity with an exposure time ranging from 1 to 8 min on a whirling arm rig. Results show that the deposited films can greatly increase the transmission of sapphire in mid-wave IR. After rain erosion test, decreases in normalized transmission were less than 1% for designed SiO2 films and the SiO2 coating was strongly bonded to the sapphire substrate. In addition, sapphires coated with SiO2 films had a higher transmittance than uncoated ones after rain erosion.

关键词： Silicon dioxide films Sapphire Magnetron reactive sputtering Rain erosion

Effect of ytterbium inclusion in hafnium oxide on the structural and electrical properties of the high-k gate dielectric

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Journal of Rare Earths 2014年第6期32卷 580-584页

作者：陈帅刘正堂冯丽萍车兴森赵小如 State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Key Laboratory of Space Applied Physics and Chemistry Ministry of Education School of Science Northwestern Polytechnical University

Abstract： The undoped and Yb-doped HfO2 thin films were deposited on p-type single crystal St（100） substrates using RF magnetron sputtering method. The structure and electrical properties were investigated as a function of doping concentrations. The results showed that the presence of Yb could stabilize HfO2 in cubic phase. The dielectric constant was enhanced after in- troducing Yb3＋ ions into the HfO2 host. Compared with undoped HfO2 thin film, the Yb-doped l-IfO2 thin film exhibited a low leakage current. The silicate reaction between rare earth ions and SiO2 layers was used to eliminate interfacial silica and form a stable interface.

关键词： HfO2 thin films dielectric rare earths

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蓝宝石衬底表面SiO2薄膜的应力分析

硅酸盐学报 2008年第2期36卷 206-209页

作者：冯丽萍刘正堂西北工业大学材料学院凝固技术国家重点实验室西安710072

采用射频磁控反应溅射法分别在Si和蓝宝石衬底上沉积SiO_2薄膜。通过改变沉积薄膜的工艺参数,考察反应气体流量比、沉积温度、射频功率等因素对SiO_2薄膜内应力的影响。采用压痕裂纹法分析了镀膜前后蓝宝石的表面应力。结果表明:制备Si... 详细信息

采用射频磁控反应溅射法分别在Si和蓝宝石衬底上沉积SiO_2薄膜。通过改变沉积薄膜的工艺参数,考察反应气体流量比、沉积温度、射频功率等因素对SiO_2薄膜内应力的影响。采用压痕裂纹法分析了镀膜前后蓝宝石的表面应力。结果表明:制备SiO_2薄膜时,工艺参数影响SiO_2薄膜的成分,当O_2/Ar流量比值为1.25,衬底温度为300℃,射频功率为100 W时,可以制备出化学计量比的SiO_2薄膜,此时薄膜中的内应力较小;制备的SiO_2薄膜呈压应力状态,镀SiO_2薄膜可以改变蓝宝石的表面应力,蓝宝石的表面应力已由原来的拉应力变为压应力。

关键词：蓝宝石二氧化硅薄膜内应力磁控反应溅射

A-La2O3电子结构和光学性质的第一性原理计算

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计算物理 2010年第5期27卷 752-758页

作者：刘其军刘正堂冯丽萍西北工业大学材料学院凝固技术国家重点实验室陕西西安710072

采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算A-La2O3的电子结构和光学性质.结果表明,A-La2O3属于间接带隙氧化物,禁带宽度为3.72 eV;其价带主要由La的5s,5p和6s态电子以及O的2s和2p态电子构成,导带主要由La的5d... 详细信息

采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算A-La2O3的电子结构和光学性质.结果表明,A-La2O3属于间接带隙氧化物,禁带宽度为3.72 eV;其价带主要由La的5s,5p和6s态电子以及O的2s和2p态电子构成,导带主要由La的5d态电子构成.经带隙校正后,计算得到A-La2O3在(100)和(001)方向上的光学线性响应函数随光子能量的变化关系,包括复介电函数、复折射率、吸收光谱、反射光谱、损失函数和光电导谱.结果表明,A-La2O3在(100)和(001)方向上具有光学各向异性,并且具有从近紫外到红外的透明区域,为A-La2O3的应用提供了理论依据.

关键词： A-La2O3 电子结构光学性质第一性原理

新型高k栅介质HfSiON薄膜的制备及性能研究

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稀有金属材料与工程 2008年第11期37卷 2008-2011页

作者：冯丽萍刘正堂田浩西北工业大学凝固技术国家重点实验室陕西西安710072

为了替代传统的SiO2栅介质,利用射频反应溅射法在Si衬底上制备了新型HfSiON薄膜。研究了HfSiON薄膜的成分、结构和介电性能。由XRD图谱可知,HfSiON薄膜经900℃高温退火处理后仍为非晶态,显示出良好的热稳定性。MOS电容的高频C-V曲线测... 详细信息

为了替代传统的SiO2栅介质,利用射频反应溅射法在Si衬底上制备了新型HfSiON薄膜。研究了HfSiON薄膜的成分、结构和介电性能。由XRD图谱可知,HfSiON薄膜经900℃高温退火处理后仍为非晶态,显示出良好的热稳定性。MOS电容的高频C-V曲线测量显示,HfSiON薄膜具有较好的介电特性,其介电常数可达到18.9,电容等效氧化层厚度为4.5nm。I-V测量结果表明,HfSiON薄膜的漏电流密度很低,在外加偏压(Vg)为±1.5V处的漏电流密度分别为3.5×10-7A/cm2(+1.5V)和1.5×10-6A/cm2(–1.5V)。研究表明,HfSiON薄膜将会是一种很有希望取代SiO2的新型高k栅介质材料。

关键词：高k栅介质 HfSiON薄膜射频反应溅射

Cmcm空间群斜方SrHfO_3的电子结构和光学性质理论计算（英文）

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稀有金属材料与工程 2016年第4期45卷 881-884页

作者：田浩冯丽萍刘正堂西北工业大学凝固技术国家重点实验室陕西西安710072

采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算了Cmcm空间群斜方SrHfO_3的电子结构和光学性质。计算得到的Cmcm斜方SrHfO_3的平衡晶格常数均与实验值相近。同时,计算得到了Cmcm斜方SrHfO_3的能带结构、态密度和电... 详细信息

采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算了Cmcm空间群斜方SrHfO_3的电子结构和光学性质。计算得到的Cmcm斜方SrHfO_3的平衡晶格常数均与实验值相近。同时,计算得到了Cmcm斜方SrHfO_3的能带结构、态密度和电荷密度。结果表明,斜方SrHfO_3属于直接带隙氧化物,在Hf和O之间主要是共价键结合而在Sr和O之间主要呈现离子键特性。计算还得到了斜方SrHfO_3的复介电函数、折射率和消光系数等,且复介电函数的实部与虚部都与实验结果接近。

关键词：电子结构光学性质斜方SrHfO3